Viro - Lecture 6

drraythe's version from 2015-08-30 15:36

Viral Vaccines

Question Answer
What are some important factors to consider w/ vaccination programs?The proportion who received the vx that are protected, the duration of protection, & coverage achieved by the program
Questions to address when it comes to vaccination programs?Is it possible to elim the infection? What proportion should be vaccinated? At what age & interval should they be vaccinated?
How come vaccinations can protect vaccinated & unvaccinated individuals?Bc opportunities for the transmission of the virus in the population as a whole are reduced
Multivalent vaccinations have two benefits she mentioned, which areReduce # of visits to the clinic, & allow extensive use of vaccines against agents of secondary importance
How can vaccines protect the fetus in utero? Which vx should be used?Vaccinate the DAM. However, attenuated (live modified) can be abortogenic/teratogenic, so you want to use inactivated vx w/ the dam
Which type of vaccination has a high chance of being abortogenic or teratogenic?Attenuated vx (aka live modified)
What are some ways chickens are vaccinated?Usually in low-cost delivery systems, such as an aerosol or in the feed. ALSO can vaccinate eggs
What are the 4 main types of vaccinations?Live virus (attenuated)
non-replicating native antigen vaccines
vx produced by recombinant DNA & other innovative technologies
DNA vx
Explain live virus vaccinated (attenuated vx). How do they develop them?Naturally occurring attenuated vx, by serial passage in cell culture, serial passage in a heterologous host animal (diff animal from the host), selecting cold-adapted mutants & assortments
Explain non-replicating native antigen vaccines. How do they develop them?Inactivated whole virions, native viral subunits, purified native viral proteins
**Explain vx produced by recombinant DNA & other innovative technologies. How do they develop them?Mainly, they take a plasmid of viral DNA & put it into a host (a bacteria, yeast, etc) & the host is injected into the animal, viral proteins are produced by the host which the animal's immune system mounts a response to.
Route of admin for live vs inactivated vx?LIVE - injection, inhalation, & oral
INACTIV - injection
Amount of virus in dose for live vs inactivated vx?LIVE - Low
Number of doses for live vs inactivated vx?LIVE - Usually one
INACTIV - Multiple
Need of adjuvant for live vs inactivated vx?LIVE - No
Duration of immunity for live vs inactivated vx?LIVE - Many years
INACTIV - 1 year or less
Antibody response for live vs inactivated vx?LIVE - IgG, & IgA (if mucosal route)
Cell mediated response for live vs inactivated vx?LIVE - Good
INACTIV - Modest
Heat lability (sensitivity to temp I think this means) for live vs inactivated vx?LIVE - Yes, for most viruses
Interference by prior antibody for live vs inactivated vx?LIVE – Yes
INACTIV - Usually no
Side effects of live vs inactivated vx?LIVE - Occasional, local or systemic
INACTIV - Occasional, local
Use in preg animals of live vs inactivated vx?LIVE - Often not advised, but commonly done
Reversion to virulence in live vs inactivated vx?LIVE - Rarely
Cost of vx, live vs inactivatedLIVE – Low
What are the routes of vx admin?Oral, intranasal, aerosol, subcutaneous, intramuscular, intravenous, intraperitoneal, intra ovo
Factors affecting vaccine efficacy are?Heat liability, vaccination frequency, physiologic & immunologic considerations (fever or hypothermia, general debilitation, very young or very old, use of GGC or cytotoxic drugs).
What are human errors surrounding vx's?Improper mixing, incorrect route, storing at high temperature & vaccinating too frequently
What are factors affecting vx safety?Underattenuation, genetic instability, contaminating viruses, adverse effects in pregnant animals, adverse effects from non-replicating vaccine, inoculation site reactions
W/ what & why do we use adjuvants?Usually use in conjunction w/ inactivated vx's. Adjuvants potentiate the immune response both humoral & cellular so less amount of antigen or fewer doses are necessary to achieve protection
What are some awesome things adjuvants do?They might prolong the release of antigen, activate macrophages who secrete lymphokines & attract lymphocytes or induce mitogenicity for lymphocytes
Why are antiviral drugs NOT used in vet med much?Cost
Viral infections in vet med are usually treated...Symptomatically & palliatively
What is acyclovir? What is it for & how does it work?It is an antiviral drug used for treating feline herpesvirus 1 corneal ulcers. It is delivered as a prodrug, & requires a viral-coded enzyme to be activated. Since it needs the viral protein, it will only be activated in infected cells, & will be non-toxic in healthy cells
What temperature do surface proteins denature? What about at ambient temp?60⁰ for denature of surface proteins. At ambient temp there is a slower but still significant decay of ineffectively
What temp would you store vx's for a day? Long term?Day = 4⁰ C or ice for one day
LONG TERM = -70 ⁰C or liquid nitrogen or lyophilized (freeze dried)
Do you want to freeze a vx?No, not ideally.
What is resistant to extreme temperatures?Prions
Which type of viruses are more resistant to acid?Enteric (stomach acid)
What type of solvents destroy viral envelopes?Lipid solvents
Sodium hypochlorite (brand names? uses? remarks?)AKA: Clorox, Chlorize. USES: Drinking water, food, (WAT?) utensils, dairies, spot disinfection. REMARKS: Very effective & cheap & nontoxic, but high levels of protein can interfere w/ effectiveness
Detergent iodophores (brand names? uses? remarks?)AKA: Betadine, Wescodyne, Redene. USES: Drinking water, food, utensils, dairies, spot disinfection. REMARKS: Expensive, less affected by high protein levels, action based on slow release of iodine & detergent (a red beta named Wes likes water & food, but an iodo of protein in the water will kill him)
Formaldehyde (brand names? uses? remarks?): AKA: Formalin. USES: Laundry, bedding surfaces, & as vapor for surface sterilization. REMARKS: Low power of penetration except as vapor, but useful for terminal disinfection, irritating, hypersensitivity might develop.
Question Answer
Phenol derivatives (brand names? uses? remarks?)AKA: Lysol, Dettol, Stephene, Sudol. USES: 2.5% in aqueous solution for hands, exam tables, cages, hospital surfaces. REMARKS: Efficacy depends on concentration & temperature. High protein conc interfere
Chlorhexidine (brand names? uses? remarks?)AKA: Hibitane, Nolvasan. USES: Wide range, exam tables, cages, hospital surfaces. REMARKS: Little effected by body fluids, soap, organic compounds. Expensive. ( I said hi nol as he cleaned the table w/ chlorohex. It was expensive, but killed everything)